Summary The Collegium Ramazzini strongly rejects the claim by Tomasetti and Vogelstein that 65% of cancers are due to “bad luck” and result from randomly acquired mutations of the genome (Tomasetti and Vogelstein 2015b). This claim is based on a skewed and highly selective reading of the literature. It examines only a fraction of cancers – 34% – in a single country – the United States (Wild et al. 2015). It ignores enormous differences in cancer incidence and mortality across countries (Wild et al. 2015) (Potter and Prentice 2015). It dismisses abundant clinical and epidemiological research that has discovered scores of environmental and occupational carcinogens to which millions of persons are exposed (Wild et al. 2015). It ignores the very great successes in cancer prevention that have been achieved by controlling exposures to known carcinogens (Ashford et al. 2015; Gotay et al. 2015; Potter and Prentice 2015; Song and Giovannucci 2015; Wild et al. 2015).

The spurious claim of Tomasetti and Vogelstein poses grave danger to public health. It has the potential to undermine governmental programs for cancer prevention and also to discourage individuals from making wise decisions to change lifestyle, diet, and other factors that can reduce exposures to carcinogens.

In rejecting the unsubstantiated claim by Tomasetti and Vogelstein, the Collegium Ramazzini is proud to join the International Agency for Research on Cancer (Wild et al. 2015) and distinguished scientists from around the world (Ashford et al. 2015; Gotay et al. 2015; Potter and Prentice 2015; Song and Giovannucci 2015). We fully endorse the IARC critique of the Tomasetti-Vogelstein report (Wild et al. 2015).

Finally, the Collegium Ramazzini notes that Tomasetti and Vogelstein failed to disclose potentially important financial conflicts of interest (Tomasetti and Vogelstein 2015b).